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Drug Therapy: Agonists

Drug therapy uses the biological approach to reduce drug and alcohol addiction. Agonists mimic the effects of drugs. Antagonists reduce the effect of the addictive drugs.

Biological effect

Biological effect

  • The biological approach to explaining addiction states that there must be a biological effect that needs to be reduced to cure the addiction.
  • Many drug addictions, like nicotine, cause dopamine, a pleasure neurotransmitter, to be released.
  • So the drug therapies apply these theories to cure the addiction.
Drug therapies

Drug therapies

  • Drug therapies want to reduce the dependency on the drugs by prescribing medications to abate the addictive behaviour.
  • These medications must be carefully monitored to prevent an addiction to the medications themselves.
Agonists

Agonists

  • Agonists are drugs which imitate or mimic the effects of the drug without having the harmful side effects.
    • An example of an agonist is methadone.
      • Methadone is an agonist to heroin.
      • It is prescribed to heroin addicts to lessen their addiction without having the painful effects of withdrawal symptoms.
Methadone

Methadone

  • Methadone works by binding the opiate receptors on neurons.
  • This stimulates the neurons, mimicking the effects of heroin (another opiate).
  • But it is less dangerous than heroin.
  • Methadone allows the heroin addicts to slowly reduce the amount of heroin they need to take.
__Newman and Whitehill (1979)__

Newman and Whitehill (1979)

  • There have been studies to prove the effectiveness of methadone.
  • Newman and Whitehill (1979) compared methadone to a placebo in heroin addicts and found methadone to be significantly more successful than the placebo.

Drug Therapy: Antagonists

Drug therapy uses the biological approach to reduce drug and alcohol addiction. Agonists mimic the effects of drugs. Antagonists reduce the effect of the addictive drugs.

Antagonists:

Antagonists:

  • These are drugs which reduce the effects of drugs like heroin or alcohol.
  • Antagonists work by blocking neuron receptors.
    • An example of an antagonist is naltrexone.
Naltrexone

Naltrexone

  • Naltrexone blocks the effects of alcohol and heroin.
  • So the positive effects of consuming the drug are reduced.
  • The addict does not feel pleasure by consuming the drugs.
  • The reinforcement (pleasurable feelings) of taking drugs is lessened. This means the habit is less likely to continue.
  • Operant conditioning (learning theory) is not an issue.
Disadvantages of drug therapy

Disadvantages of drug therapy

  • The drug therapy method does have disadvantages:
  • The addict could potentially develop an addiction to the drug that is trying to help them.
    • This has been known to happen with methadone.
Side effects

Side effects

  • There are also other side effects of taking the drugs.
    • For example, naltrexone can cause skin rash, and less commonly: fever, weight gain, depression, and chest pain among others.
Short-termist

Short-termist

  • Finally, if the person stops taking the replacement drug, they could potentially develop the addiction again (relapse).
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